Viral-Like Particles Are Associated With Endosymbiont Pathology in Florida Corals Affected by Stony Coral Tissue Loss Disease

Stony coral tissue loss disease (SCTLD) was first documented in 2014 near the Port of Miami, Florida, and has since spread north and south along Florida’s Coral Reef, killing large numbers of more than 20 species of coral and leading to the functional extinction of at least one species, Dendrogyra cylindrus. SCTLD is assumed to be caused by bacteria based on presence of different molecular assemblages of bacteria in lesioned compared to apparently healthy tissues, its apparent spread among colonies, and cessation of spread of lesions in individual colonies treated with antibiotics. However, light microscopic examination of tissues of corals affected with SCTLD has not shown bacteria associated with tissue death. Rather, microscopy shows dead and dying coral cells and symbiotic dinoflagellates (endosymbionts) indicating a breakdown of host cell and endosymbiont symbiosis. It is unclear whether host cells die first leading to death of endosymbionts or vice versa. Based on microscopy, hypotheses as to possible causes of SCTLD include infectious agents not visible at the light microscopy level or toxicosis, perhaps originating from endosymbionts. To clarify this, we examined corals affected with SCTLD and apparently healthy corals using transmission electron microscopy. Endosymbionts in SCTLD-affected and apparently healthy corals consistently had varying degrees of pathology associated with elongated particles compatible in morphology with filamentous positive single-stranded RNA viruses of plants termed anisometric viral-like particles (AVLP). There was apparent progression from early to late replication of AVLP in the cytoplasm of endosymbionts adjacent to or at times within chloroplasts, with morphologic changes in chloroplasts consistent with those seen in plant cells infected by viruses. Coral host cell pathology appeared limited to massive proliferation and lysis of mucus cells. Based on these findings, we hypothesize that SCTLD is a viral disease of endosymbionts leading to coral host death. Efforts to confirm the presence of a virus associated with SCTLD through other means would be appropriate. These include showing the presence of a virus through molecular assays such as deep sequencing, attempts to grow this virus in the laboratory through culture of endosymbionts, localization of virus in tissue sections using immunohistochemistry or in situ hybridization, and experimental infection of known-virus-negative corals to replicate disease at the gross and microscopic level.

Rapid Population Decline of the Pillar Coral Dendrogyra cylindrus Along the Florida Reef Tract

Coral reefs worldwide are in a state of decline, but the population status and impacts of stressors for rare species are generally not well documented using broad-scale monitoring protocols. We fate-tracked all known colonies of the pillar coral, Dendrogyra cylindrus, on the Florida Reef Tract (FRT) from 2013 to 2020 to assess population condition and trend, and to document the relative impacts of chronic and acute stressors. Large average colony size, an absence of juveniles, and large geographic distances between genotypes suggest that the Florida D. cylindrus population has been reproductively extinct for decades. During the study period, low-intensity chronic stressors were balanced by regrowth, while back-to-back years of coral bleaching and thermally-exacerbated disease led to declines that the subsequent recovery rates suggest would require 11 uninterrupted years to overcome. The most recent stressor on Florida’s D. cylindrus population is “stony coral tissue loss disease” (SCTLD). Following the appearance of the disease in Florida in 2014, unrecoverable losses occurred within the D. cylindrus population as tissue, colonies, and whole genotypes suffered complete mortality. Losses of 94% of coral tissue, 93% of colonies, and 86% of genotypes between 2014 and the end of 2020 have led to functional extinction of D. cylindrus on the FRT.

The northern bald ibis Geronticus eremita: history, current status and future perspectives

The northern bald ibis Geronticus eremita was once widespread throughout the Middle East, northern Africa, and southern and central Europe. Habitat destruction, persecution and the impacts of pesticides have led to its disappearance from most of its former range. It disappeared from central Europe > 400 years ago, but has persisted as a relict and slowly growing breeding population in Morocco, where c. 700 wild birds of all ages remain. In Algeria, the last confirmed breeding was in 1984; in Turkey the fully wild population disappeared in 1989, but a population remains in semi-wild conditions. In Syria a small population was rediscovered in 2002, only to subsequently decline to functional extinction. Restoration programmes have been initiated independently in several locations, with over 300 free-flying birds resulting from reintroduction projects in Austria, Germany, Spain and Turkey, to restore both sedentary and fully migratory populations. Maintaining current efforts in Morocco remains a high conservation priority.

A Retrospective Analysis on the Population Viability of the Yangtze River Dolphin or Baiji (Lipotes vexillifer)

Background: Lipotes vexillifer, is a functionally extinct species of freshwater dolphin commonly called as Baiji dolphin of Yanzte River, China. The dolphin is thought to be the first one of it’s kind driven to extinction due to the impact of humans. Yangtze Freshwater Dolphin Expedition carried out in the year 2006 revealed the species as functionally extinct. The présent study deals with the population viability analysis of the baiji dolphin using Vortex software and also by consulting historical materials and relevant literature to explore the possible causes of the functional extinction of the baiji in the Yangtze River. The findings are to provide guidance for the effective management of another freshwater mammal, the Yangtze finless porpoise. Methods: Population viability analysis of the baiji dolphin for various parameters were assessed using Vortex software and other published information and relevant literatures. The analysis were carried out to ascertain the possible causes of the functional extinction of the baiji in the Yangtze River. Result: Simulation models were employed to identify the reasons for extinction of Yangtze River baiji population by adopting viability retrospective method. The various parameters associated with the population analysis were included to derive logical conclusion. The minimum viable population of the Yangtze River baiji was also identified by adopting various simulation models. The present study is the first attempt to apply the 10,000-time iteration method to the baiji population survivability analysis.

Rapid Population Decline of the Pillar Coral Dendrogyra cylindrus Along the Florida Reef Tract

Coral reefs worldwide are in a state of decline, but the status of populations and stressors for rare species are generally not well documented using broad-scale monitoring protocol. We fate-tracked all known colonies of the pillar coral Dendrogyra cylindrus on the Florida Reef Tract from 2013 – 2020 to assess the population and document the impacts of chronic and acute stressors. Large average colony size, an absence of juveniles, and large geographic distances between genotypes suggest that the Florida D. cylindrus population has been reproductively extinct for decades. During the study period, low-intensity chronic stressors were balanced by regrowth, while back-to-back years of coral bleaching and thermally-exacerbated disease led to declines that the subsequent years of recovery suggest would take 11 uninterrupted years to overcome. The most recent stressor on Florida’s D. cylindrus population is “stony coral tissue loss disease.” Following the appearance of the disease in Florida in 2015, it resulted in unrecoverable losses to the D. cylindrus population as tissue, colonies, and whole genotypes were driven to extinction. Losses of 91% of coral tissue, 88% of colonies, and 73% of genotypes between 2014 and early 2020 have led to functional extinction of D. cylindrus on the Florida Reef Tract.

What Makes a Panther a Panther?

Species categorizations can involve both scientific input and conservation questions about what should be preserved and how. We present a case study exploring the social construction of species categories using a real-life example of a cougar subspecies (Puma concolor stanleyana) purposefully introduced into Florida to prevent the functional extinction of a related subspecies of panther (P. c. coryi). Participants in an online sample (n = 500) were asked to make categorization decisions and then reflect on those decisions in an open format. Analysis of coded responses suggest people may experience “species” as both a social and biological construct, and that the question of what species people think an animal belongs to cannot be answered in isolation from questions about how that animal fits into larger social and biological systems.

Habitat degradation and indiscriminate hunting differentially impact faunal communities in the Southeast Asian tropical biodiversity hotspot

Habitat degradation and hunting have caused the widespread loss of larger vertebrate species (defaunation) from tropical biodiversity hotspots. However, these defaunation drivers impact vertebrate biodiversity in different ways and, therefore, require different conservation interventions. We conducted landscape-scale camera-trap surveys across six study sites in Southeast Asia to assess how moderate degradation and intensive, indiscriminate hunting differentially impact tropical terrestrial mammals and birds. We found that functional extinction rates were higher in hunted compared to degraded sites. Species found in both sites had lower occupancies in the hunted sites. Canopy closure was the main predictor of occurrence in the degraded sites, while village density primarily influenced occurrence in the hunted sites. Our findings suggest that intensive, indiscriminate hunting may be a more immediate threat than moderate habitat degradation for tropical faunal communities, and that conservation stakeholders should focus as much on overhunting as on habitat conservation to address the defaunation crisis.

ПРИЙМЕННИК ДѢЛӔ В УКРАЇНСЬКІЙ МОВІ XVI-XVII СТОЛІТЬ: ОСОБЛИВОСТІ ГРАМАТИКИ ТА СЕМАНТИКИ

The article analyzes the grammar point, which deals with question of functioning of the prepositions in the Ukrainian language from the XVI–XVIІ centuries, including works explored by L. Zyzanii, M. Smotrytskyi. Although these reviewed works do not contain any information about preposition дѣлӕ at that time, I. Uzhevych’s grammar fixes its variant длӕ. Dictionary of the Old Ukrainian language of the XIV–XV centuries indicates that the language unit дѣлӕ used as a preposition that expresses relations of purpose in postposition to noun and relations of cause in front position regarding the noun. Dictionary of the Ukrainian language of the XVI – first half of XVII century presents wider semantic structure of the preposition дѣлѧ (дѣля, дилѧ, диле, дѣли): purpose, cause and object relations. Also the article presents the specifics of functioning of the derivative preposition дѣлӕ, describes its paradigmatic relation-ships. The research based on the materials of Lviv Stauropegion Brotherhood documents dated the XVI–XVIІ centuries. It is examined a semantic structure, shown the compatibility of investigated preposition with the genitive case. We found that the largest part of preposition constructions with genitive case expressing the aim of action. Apart from that, there is one more specific feature: this linguistic unit could use before noun and after it, while the most of prepositions stand in front of the noun or pronoun. Preposition дѣлӕ has not broad semantic relationships: with the genitive case it expresses only two types of semantic relations (we submit it to the frequency of use): purpose and cause. In comparison with functioning of the preposition длӕ investigated preposition had narrow semantic structure and less extensive coverage in the texts of Lviv Stauropegion Brotherhood documents. In fact, we observe the process of functional extinction of the preposition дѣлӕ. Although it belonged to a very ancient language units, it archaized and did not use in the contemporary Ukrainian language.